Scuba divers use an air tank with a valve head at one end having a passage leading from the interior of the tank to an outlet port in one side of the valve head. An outlet flow regulator for regulating the air flow to the diver's breathing mask is releasably attached to this valve head. To provide a fluid-tight seal between the valve head and the outlet flow regulator, an O-ring of rubber-like material is seated in an annular groove surrounding the outlet port in the side of the valve head. The outlet flow regulator has a rigid annular projection on its inlet side which extends into this groove and deforms the O-ring to provide an effective seal when the outlet flow regulator is attached to the valve head. When the outlet flow regulator is removed from the valve head the O-ring may pop out or drop out of the groove.
The present invention is directed toward the solution of this problem plus providing protection for external and internal portions of the head valve.
The following U.S. patents were found in a novelty search on the present invention: U.S. Pat. Nos: Maack 3,021,034; Kessler 3,067,900; Martin et al 3,937,442; Lorenz 1,512,347; and Vouillemin 3,920,143.